quick question about city expansion

[waterwaterwater]

So I understand to expand a settlement I need to have the proper level of population. However, as far as I can tell the population bar is for the entire province and not just a single region. How does this make sense that I have to wait for the entire region to increase in population, even if I don't own the entire province? If the ai increases the size of their cities does it lower the population thus blocking me from expanding?

[Chromium]

Nope. As far as I can make out, the population growth in your regions is independent to that of the AI, irrespective of what provinces you & they own.

IMO, the entire system is actually pretty retarded but that's another topic.